Fast fashion and online retailing are growing at incredible rates. Simultaneously, Generation Y and Z consumers are becoming increasingly important generational cohorts to understand due to their population size and growing spending power. This quantitative research study explores the salient apparel and key online retailing cues used during decision-making by a Canadian consumer sample of 416 individuals, from both generational cohorts, when shopping online for fast fashion. Data collected is also used to make preliminary findings on online promotional and advertising cues used by both generational cohorts. Shopping behaviour is clustered to provide actionable insight, and retailer recommendations are made based on data collected from this study. An online questionnaire survey has been used to collect data, and IBM Statistical Package for Social Sciences (SPSS) software was used to analyze all data sets.